Print all objects in a workspace

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Solution 1

Do you mean 'display' in the sense of "for every object in ls(), I want to see what I would see if I typed it into the prompt"? What if you have some matrix that's 1000x10000 - you still want to print it? I personally like ls.str() - I think it gives a nice concise overview of everything, and handles the case I just mentioned nicely.

However if you want to basically "display" every object in the sense of typing each on the prompt, I'd suggest a loop:

for ( obj in ls() ) { print(get(obj)) }

Since ls() returns a character vector of variable names, I need to use get(obj) which gets the variable whose name is in obj.

You may wish to do a variation of this in order to print the variable name too, e.g.

for ( obj in ls() ) { cat('---',obj,'---\n'); print(get(obj)) }

As an example:

> a <- 1
> b <- LETTERS[1:10]
> c <- data.frame(a=LETTERS[1:10],b=runif(10))
> for ( obj in ls() ) { cat('---',obj,'---\n'); print(get(obj)) }
--- a ---
[1] 1
--- b ---
 [1] "A" "B" "C" "D" "E" "F" "G" "H" "I" "J"
--- c ---
   a         b
1  A 0.1087306
2  B 0.9577797
3  C 0.8995034
4  D 0.1434574
5  E 0.3548047
6  F 0.1950219
7  G 0.1453959
8  H 0.4071727
9  I 0.3324218
10 J 0.4342141

This does have a drawback though - next time you call ls() there's now an obj in there. I'm sure there's some workaround though.

Anyhow, I think I still prefer ls.str() for the way it handles big objects (but I work with a lot of huge (millions of elements) matrices, so that's my preference).

Solution 2

If you just want the names of the variables you use:

ls()

If you want to print your variables along with the contents as well then use the command:

mget(ls())

This should do what you need.

For a fresh-opened workspace with some matrices, vectors, and data-frames it works well for me.

Solution 3

I find that using RStudio allows me a view on all objects in the environment and direct interaction with each. I am sure that a good IDE will allow the sort of exploration that your question seems to require. This would especially be useful to give you a view on a large number of objects.

Solution 4

Trust me: you really don't want to print all the contents of all your objects. Just imagine printing out matrix(1:1e5,100,1000) :-( . There are some useful R tools like summary , table, and str which generally tell you enough about a data object for you to know what it is and what you want to do with it. If you have more specific concerns, e.g., "Which of my dataframes have NA values?" , you can write commands or mini-functions to do the looking.
I wrote some for myself with names like lstype(objtype='closure') , which lists all objects of the designated kind.

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Rico
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Rico

Updated on September 17, 2020

Comments

  • Rico
    Rico over 3 years

    I cannot find out how to list and print all objects in a workspace. I'd like to see them all and understand what's going on. For example, ls() gives you 30 objects. How, besides typing them individually, is it possible to display them all. Seems so trivial, the solution will probably quite embarrasing. The closest I've come was ls.str() and the idea of looping over the objects.

    Edit: This is not for data frames. I have a workspace full of functions, without data, and like to understand which ones reference which etc.

  • andilabs
    andilabs over 10 years
    ATTENTION: running for ( obj in ls() ) { print(get(obj)) } may cause that your R gets freezed if you have a really long session with R.
  • helen.h
    helen.h about 8 years
    Is there a way to just print a list of selected objects from the workspace?